CVE-2026-16347 (GCVE-0-2026-16347)
Vulnerability from cvelistv5 – Published: 2026-07-28 19:59 – Updated: 2026-07-29 13:57
VLAI
EPSS
VEX
Title
Improper restriction of excessive authentication attempts in MikroTik RouterOS and Cloud Hosted Router
Summary
MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-29 13:57 UTC
CWE
- CWE-307 - Improper restriction of excessive authentication attempts
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://www.cisa.gov/news-events/ics-advisories/i… | government-resource |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| MikroTik | RouterOS |
Affected:
All versions
|
guessed | |
| MikroTik | Cloud Hosted Router |
Affected:
All versions
|
guessed |
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